Planar electromagnetic metamaterial with a fish scale structure.

We report on a continuous electromagnetic metal planar metamaterial, which resembles a "fish scale" structure. Apart from the one isolated wavelength, it is highly transparent to electromagnetic radiation throughout a broad spectral range and becomes completely "invisible" at some frequency inflicting no transmission losses and phase delay. When the structure is superimposed on a metallic mirror it becomes a good broadband reflector everywhere apart from one wavelength where the reflectivity is small. At this wavelength the reflected wave shows no phase change with respect to the incident wave, thus resembling a reflection from a hypothetical zero refractive index material, or "magnetic wall." We also discovered that the structure acts as a local field concentrator and a resonant "amplifier" of losses in the underlying dielectric.